Sole Structure of Footwear

ABSTRACT

The present invention provides a sole structure of footwear which makes it possible for a user to walk in a special position such that a toe part is in a raised state, thus providing an exercise effect, and is constructed such that the inclination of the footwear can be smoothly changed forwards and backwards based on a metatarsal bone part, so that the user can naturally conduct exercise. To achieve the above purposes, the present invention comprises a main sole, which has an outline that approximately corresponds to an outline of a foot sole, a front cushion sole, which is coupled to a portion of the main sole which is ahead of the metatarsal bone part, and a rear cushion sole, which is coupled to a portion of the main sole which is behind of the metatarsal bone part.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates, in general, to sole structures of footwear and, more particularly, to a sole structure of footwear in which several sole parts made of different materials are three-dimensionally coupled together to form the sole of the footwear, so that, when a user wears the footwear, the sole structure provides a mountain climbing effect, as if the user were climbing an upward slope, and which provides superior wearing comfort and a pleasant feeling, and has sufficient shock absorbing ability, thus protecting the joints and ankle of the user.

2. Description of the Related Art

Generally, footwear serves to protect the feet of a user and to absorb shocks transmitted to the user when the user walks. The footwear includes a sole, which forms a bottom layer, and an upper, which is coupled to the sole to cover the foot of the user. Typically, the sole may have a single sole structure which is covered with an insole, or, alternatively, may have a structure such that a midsole is coupled to the upper surface of an outsole and an insole is provided on the midsole.

Such a sole of footwear typically has a structure in which a heel part thereof is slightly thicker than a toe part. Furthermore, the sole has a consistent structure and is uniformly made of the same material from the heel part to the toe part, thus having even cushioning ability.

However, when the user wears the footwear having the conventional sole structure and walks, because only muscles that are normally used are used, it is difficult to obtain a special exercise effect.

Recently, there has been proposed a sole, which is uniformly made of the same material and is designed such that a heel part is lower than a toe part so that, when walking, the toe part maintains a raised state, thus providing an exercise effect, like when climbing a mountain, even when the user walks a level ground.

However, in the case of the conventional exercise footwear, as a result of regarding only the exercise effect as being important, the wearing comfort of the footwear is poor, thus being uncomfortable to the user. Furthermore, with regard to the design for enhancing shock absorbing ability, the conventional footwear has only a basic cushioning function, and thus the exercise effect is reduced, that is, an optimal balance between the exercise effect and wearing comfort is not realized. In addition, there is a problem in that the shape of the footwear is too different from that of typical footwear to wear it at normal times.

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a sole structure of footwear which makes it possible for a user to walk in a special manner such that a toe part is in a raised state, thus providing an exercise effect, and is constructed such that the inclination of the footwear can be smoothly changed forwards and backwards on the basis of a metatarsal bone part, so that the user can naturally conduct exercise, and which, more particularly, ensures superior wearing comfort and a pleasant feeling and has an external appearance that is not different from that of typical footwear.

In order to accomplish the above object, the present invention provides a sole structure of footwear, including: a main sole having an outline corresponding to an outline of a foot sole of a user; a front cushion sole coupled to a portion of the main sole that is ahead of a metatarsal bone part of the main sole; and a rear cushion sole coupled to a portion of the main sole which is behind the metatarsal bone part. The front and rear cushion soles are compressed by weight of the user ahead of and behind the metatarsal bone part, so that inclination of the entire sole is changed based on the metatarsal bone part.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is an exploded perspective view of a sole structure of footwear, according to an embodiment of the present invention;

FIG. 2 is a view taken along line A-A′ of FIG. 1 to show the interior and exterior of the footwear having the sole structure according to the present invention;

FIG. 3 is a view showing the state of the sole of the present invention when the user wearing the footwear is walking;

FIG. 4 is a view showing the state of the sole of the present invention when a user wearing the footwear is standing;

FIG. 5 is a sectional view, taken along line B-B′, showing another embodiment of the footwear having the sole structure of the present invention;

FIG. 6 is an exploded perspective view of a sole structure of footwear, according to another embodiment of the present invention;

FIG. 7 is a sectional view of the footwear having the sole structure of FIG. 6;

FIGS. 8 a and 8 b are views showing various modifications of the sole structure of the footwear according to the present invention;

FIGS. 9 a through 9 c are views showing the interiors and exteriors of footwear having the sole structures of the present invention; and

FIGS. 10 a through 10 c are views showing various modifications of the footwear having the same effect as the sole structure of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

A sole structure of footwear according to the present invention includes a main sole 100, a front cushion sole 200, and a rear cushion sole 300, which are made of different materials to provide different cushioning abilities.

Referring to FIG. 1, showing the embodiment of the present invention, the main sole 100 serves as a main frame of the sole structure. The main sole 100 has an outline corresponding to the shape of the sole of the foot of a user and is made of relatively hard material having appropriate elasticity such that it is merely bent when the user walks, thus supporting the weight of the user.

The main sole 100 has a metatarsal bone part 110, which is thickest, and a front part 120 and a rear part 130, which are relatively thin and are provided ahead of and behind the metatarsal bone part 110. Here, each of the front part 120 and the rear part 130 is angled upwards and gradually becomes thinner from the boundary of the metatarsal bone part 110 to the end thereof, so that the absolute height thereof is increased from the metatarsal bone part 110 to the end.

Furthermore, the front cushion sole 200 and the rear cushion sole 300 are respectively attached to the front part 120 and the rear part 130 of the main sole 100, which are reduced in thickness, thus forming the shape such that the entire sole has an approximately even thickness.

The front cushion sole 200 and the rear cushion sole 300 are made of material having superior elasticity, so that, when the user wears the footwear and walks, the front cushion sole 200 and the rear cushion sole 300 serve as cushions ahead of and behind the metatarsal bone part 110 such that the main sole 100 acts as a seesaw based on the metatarsal bone part 110.

In detail, when the weight of the user compresses the relatively hard main sole 100, the main sole 100 is inclined backwards because the rear cushion sole 300 absorbs the weight of the user. At this time, the main sole 100 is inclined backwards around the metatarsal bone part 110, which is supported, but not by a cushion sole, and thus serves as a pivot. Here, because the main sole 100 is made of hard material, the entire length of the main sole 100 is inclined without being bent. Particularly, because the rear cushion sole 300 has a structure such that the thickness thereof is increased from the front end to the rear end, sufficient inclination is ensured.

As such, when the main sole 100 is inclined backwards while the user wears the footwear, because the center of gravity is moved backwards, the user uses special muscles, which are seldom used, to maintain the weight balance, thus reinforcing the muscles, thereby obtaining the effect of exercise. Here, it will be easily understood that, as the backward inclination is increased, the effect of exercise is also increased.

Meanwhile, typically, the lateral gravity centers of the legs of a person are disposed at outer portions of the feet rather than at the central portions of the feet.

Therefore, when the user wear the footwear of the present invention, the rear cushion sole 300, which provides cushioning, is not evenly compressed in a lateral direction, that is, because the center of gravity is positioned outside, the rear cushion sole 300 is unevenly compressed. As a result, there may be problems in that the footwear becomes damaged and the legs of the user become bent.

To prevent these problems, as shown in FIG. 5, in the present invention, the rear cushion sole is divided into inner and outer parts, which are arranged in a lateral direction and are made of different materials. Here, the outer part 310 is made of material that is harder than that of the inner part 320, so that the inner part 320 is compressed more by the weight. Therefore, the rear cushion sole 300 can be evenly compressed in a lateral direction.

Meanwhile, when the user walks, the center of gravity of the user's body is shifted to the front portion of the body. That is, the center of gravity of the user is shifted from the rear cushion sole 300 to the metatarsal bone part 110, while the weight, which has been applied to the rear cushion sole 300, is gradually removed therefrom. When the center of gravity of the user is further shift to the front portion, the center of gravity of the user is shifted to the front cushion sole 200. Thus, the weight of the user is applied to the front cushion sole 200, so that the front cushion sole 200 elastically contracts. As a result, the main sole 100 is steeply inclined forwards around the metatarsal bone part 110, which serves as the pivot, compared to the typical footwear.

As described above, in the case where the main sole 100 is relatively steeply inclined forwards compared to typical footwear, the center of gravity of the user is also leaned forwards. Therefore, the user also uses special muscles, which have been seldom used, to maintain the weight balance, thus reinforcing the muscles, thereby obtaining the effect of exercise.

As such, because the present invention has a structure such that the thickness of each of the front cushion sole 200 and the rear cushion sole 300 is increased from the metatarsal bone part 110 to the end thereof, the footwear is prevented from being excessively depressed by the cushions when the user walks. Hence, the present invention provides a superior exercise effect and is comfortable to wear.

Meanwhile, as shown in FIG. 1, the sole structure of the footwear according to the present invention may be constructed such that the heel of the user is brought into direct contact with the rear cushion sole 300 to provide higher cushioning ability to the user.

In detail, an opening 140 having a predetermined size is formed through the main sole 100 at a position corresponding to the heel of the user. A protrusion 330 is provided on the rear cushion sole 300 at a position corresponding to the opening 140, so that the protrusion 330 protrudes through the opening 140 such that the heel of the user is brought into direct contact with the rear cushion sole 300, having the superior elasticity, rather than with the main sole 100, which is relatively hard.

Therefore, in addition to the function in which the inclination of the main sole 100 is changed by the cushion soles when the user walks, the rear cushion sole 300 provides the cushioning ability to the heel of the user, thus preventing the foot and joints of the user from injury, maintaining the position of the backbone correct, and making it possible to walk with correct posture.

Furthermore, the sole structure of the footwear according to the present invention may have a pumping structure such that air is pumped into the footwear by walking, thus enhancing the pleasant feeling.

Referring to FIG. 6, a first pump defining seat 190, which is concave upwards, is provided in a heel portion of a main sole 100 that corresponds to the heel of the user. A second pump defining seat 340, which is concave downwards and corresponds to the first pump defining seat 190, is formed in a heel portion of a rear cushion sole 300 that corresponds to the heel of the user. Thus, when the rear cushion sole 300 is attached to the main sole 100, a sealed space is defined by the first and second pump defining seats 190 and 340.

Furthermore, a tube 600 is provided such that a first end thereof is disposed in the sealed space. Thus, when the weight is applied to the heel portion of the sole while the user walks, the sealed space is compressed, thereby air is pumped outside the sealed space through the tube 600.

Here, because the tube 600 is seated into a tube seating groove 195, which is formed in the main sole 100, the tube 600 does not decrease the wearing comfort of the footwear. A second end of the tube 600 is disposed in an air circulation hole 160, which is provided at a position corresponding to arch parts of the toes, so that pumped air is discharged both into an air tunnel 150 and into a space defined by the arch parts of the toes, thus enhancing the pleasant feeling.

In addition, to prevent the heel part of the sole from being excessively depressed by the pump structure, a support boss 350 may be provided at the center on the second pump defining seat 340. That is, the support boss 350 serves to support the weight of the user and prevent the heel part of the sole from being excessively depressed.

Meanwhile, in the sole structure of the footwear according to the present invention, the front cushion sole 200 and the rear cushion sole 300, which are separate from each other, may be attached to the main sole 100. Alternatively, more preferably, as shown in FIG. 6, the front cushion sole 200 and the rear cushion sole 300, which are integrally manufactured into a single body unified by a thin connection part 250, may be attached to the main sole having a seating depression, into which the connection part 250 is seated, thus being easy to manufacture, ensuring reliable coupling ability between the main sole and the front and rear cushion soles, and reinforcing the cushioning ability of the metatarsal bone part.

Although the rear cushion sole has been illustrated as being coupled to the lower surface of the main sole behind the metatarsal bone part in the above embodiments, the present invention is not limited to this. That is, as shown in FIGS. 8 a and 8 b, a rear cushion sole may be coupled to the upper surface of a main sole. Furthermore, as shown in FIGS. 9 a through 9 c, a rear cushion sole may be coupled to a main sole in various other manners.

In addition, as shown in FIGS. 10 a through 10 c, a structure such that some of the cushion sole is removed from the sole structure of the present invention can also have effects similar to the present invention.

Meanwhile, the sole structure of the footwear according to the present invention may further have air tunnels 150 and air circulation holes 160.

Preferably, the air tunnels 150 are formed by covering grooves, which are laterally formed in a toe arch part and a sole arch part of the main sole 100 to which the front and rear cushion soles 200 and 300 are respectively attached, using the front and rear cushion soles 200 and 300. The several air circulation holes 160 extend from each air tunnel 150 to the upper surface of the main sole 100.

In the present invention, having the air tunnels 150 and the air circulation holes 160, when the user walks, the air tunnels 150 are expanded and contracted by the bending of the main sole 100, thus pumping air. Thereby, moisture and heat, which are generated around the arch parts of the toes and the arch part of the sole of the foot of the user, are removed by air that passes through the air circulation hole 160, thus maintaining pleasant conditions in the footwear, preventing athlete's foot, and removing foot odor.

In the case of the sole structure having the above-mentioned construction, it is preferable that an insole 500 have air circulation openings 510 at positions corresponding to the air circulation holes 160 such that the insole 500 does not impede air circulation.

Meanwhile, the metatarsal bone part 110 of the main sole 100 is made of relatively hard material to serve as a pivot when the front and rear cushion soles 200 and 300 are alternately compressed while the user walks. Here, a plurality of seating holes 170 may be formed in the metatarsal bone part 110 of the main sole 100 within a range that does not impede the function of metatarsal bone part 110.

The seating holes 170 may be maintained in the empty state to save material and reduce the weight of the shoe. Preferably, the seating holes 170 are filled with health substances 180, such as water vein wave-intercepting material, natural jade, clay, bioceramic, hard charcoal, etc., which generate ingredients that are beneficial to health and remove moisture and odor, thus being good for the health of the user.

In the sole structure according to the present invention having the above-mentioned construction, the main sole 100 and the front and rear cushion soles 200 and 300 may be integrally coupled to each other, thus forming a single outsole to be coupled to an upper 400 to form footwear. Alternatively, they may form a midsole, and the midsole is thereafter coupled to a separate outsole to form footwear. Furthermore, they may form the sole structure using any other method by those skilled in the art.

In the footwear according to the present invention, the sole is coupled to the upper such that it seems that the heel part is higher than the front part in a manner similar to typical footwear, thus ensuring the superior appearance of the footwear, despite having the sole structure described above.

As described above, the present invention provides a sole structure of footwear which makes it possible for a user to walk in a special manner such that a toe part is in a raised state, thus providing an exercise effect, and is constructed such that the inclination of the footwear can be smoothly changed forwards and backwards on the basis of a metatarsal bone part, so that the user can naturally conduct exercise. Furthermore, the present invention ensures superior wearing comfort and a pleasant feeling. In addition, the footwear having the sole structure of the present invention has an external appearance which is not different from that of typical footwear.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. 

1. A sole structure of footwear, comprising: a main sole having an outline corresponding to an outline of a foot sole of a user; a front cushion sole coupled to a portion of the main sole that is ahead of a metatarsal bone part of the main sole; and a rear cushion sole coupled to a portion of the main sole which is behind the metatarsal bone part, wherein the front and rear cushion soles are compressed by weight of the user ahead of and behind the metatarsal bone part, so that inclination of the entire sole is changed based on the metatarsal bone part.
 2. The sole structure of the footwear according to claim 1, wherein the rear cushion sole is coupled to a lower surface of the portion of the main sole which is behind the metatarsal bone part.
 3. The sole structure of the footwear according to claim 2, wherein the front cushion sole is increased in height from a rear end thereof to a front end thereof, and the rear cushion sole is increased in thickness from a front end thereof to a rear end thereof.
 4. The sole structure of the footwear according to claim 3, wherein an opening is formed through a heel portion of the main sole, which corresponds to a heel of the user, and a portion of the rear cushion sole, which corresponds to the opening of the main sole, protrudes upwards to directly contact the heel of the user.
 5. The sole structure of the footwear according to claim 3, wherein a heel portion of the main sole and a portion of the rear cushion sole that corresponds to the heel portion of the main sole form a sealed space therebetween, the sole structure further comprising: a tube disposed at a first end thereof in the sealed space and exposed at a second end thereof outside the sealed space.
 6. The sole structure of the footwear according to claim 5, wherein a support boss is provided at a center position in the sealed space to support the weight of the user, thus preventing the heel portion from being rapidly depressed.
 7. The sole structure of the footwear according to claim 6, wherein the second end of the tube is disposed at a position corresponding to arch parts of toes.
 8. The sole structure of the footwear according to claim 1, wherein the rear cushion sole is coupled to an upper surface of the portion of the main sole which is behind the metatarsal bone part.
 9. The sole structure of the footwear according to claim 3, wherein an air tunnel is laterally formed in each of portions of the main sole that contact the front and rear cushion soles.
 10. The sole structure of the footwear according to claim 9, wherein an air circulation hole extends from each of the air tunnels to the upper surface of the main sole.
 11. The sole structure of the footwear according to claim 10, wherein the air tunnels are formed in portions of the main sole that correspond to the arch parts of the toes and an arch part of the foot sole.
 12. The sole structure of the footwear according to claim 11, further comprising: an insole having air circulation openings at positions corresponding to the air circulation holes. 